Hello,
I have the following situation:
I create a class by means of Class::Base mechanism.

The method init() should be overriden in order to initialize my own object: 

sub init
{
    my ($self, $config) = @_;
    @$self{ keys %$config } = values %$config;
    $self->{ sql } = $SQL;
    $self->connect( ) || return;
    return $self;
}

[download]

This method it is called internally by the new() constructor, where bless function returns the reference object associating the reference to the anonymous hash with invocant $class, thus all accesses to the internal glob of data will be through the invocant $class.

Next, init() method it is called: 

$self->init($config);

[download]

This is the new() constructor taken from the source: 

sub new {
    my $class  = shift;

    # allow hash ref as first argument, otherwise fold args           
+  
    # into hash
    my $config = defined $_[0] && 
          UNIVERSAL::isa($_[0], 'HASH')
          ? shift : { @_ };

    no strict 'refs';
    my $debug = defined $config->{ debug }
                      ? $config->{ debug }
              : defined $config->{ DEBUG }
                      ? $config->{ DEBUG }
                      : ( ${"$class\::DEBUG"} || 0 );

    my $self = bless {
        _ID    => $config->{ id } || $config->{ ID } 
                  || $class,
        _DEBUG => $debug,
        _ERROR => '',
    }, $class;

    return $self->init($config)
        || $class->error($self->error());
}

[download]

My question is: What does the following line of code : 

@$self{ keys %$config } = values %$config;

[download]

Because it seems to dereference an array that is a value in the hash refered to by $self.

But keys %$config, returns an array of keys from the dereferenced hash refered to by $config and values %$config, returns an array of values from the dereferenced hash refered to by $config.

Is this creating pairs such thsi key_i => [value_i] foreach key and value elements?

Could anybody translate for me that line of code, please?

Thank you

20060906 Janitored by Corion: Removed H2, Added formatting, remoded code tags, as per Writeup Formatting Tips

In reply to Hash assignment misunderstanding by Anonymous Monk

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